The present invention relates to an axially operated switch for electrical circuits, which can be used in rearview mirrors or other devices in particular those which do not normally stay in front of operators.
Switches for electrical circuits and in particular axially operated switches or push-button switches are known. In such switches a key is mounted on one end of a rod which extends through a return spring and has an opposite end operating electric contacts located in a box or structure and connected to electrical connection terminals. The operation of such switches is performed by pressing the key in a direction which is coaxial to the rod, forcing the rod to move against the spring to a point in which it changes the state of commutation of the electric contacts. When the key is released the spring pushes the rod and the key to the initial position without changing the reached state of commutation. It is clear that the most favorable position for operation of the switch is when the user's finger is in a coaxial position with respect to the rod. However, in practice this is not always possible. Therefore the mechanical portion of the switch may be submitted to lateral stresses and to undesirable friction and wear.
Many electrical and electronic devices, especially those of the type used in automotive vehicles and provided with push-button switches, such as radio and television sets, turn light control switches, lighting switches and others, are located in front of or sideways of the driver. Therefore they can be operated by the driver without jeopardizing the driving of the vehicle. The key-rod assembly of such switches is generally pressed in a slanted direction in respect to the geometric axis of the rod, submitting it to a lateral stress and as a result to a determinate amount of friction against the sliding seat, which tends to wear to whole assembly during its lifetime. Recognizing the above mentioned problems, the operators of electrical and electronic devices having push-buttons which are to be reached from a lateral position very often and intuitively tend to put their finger in a position which is coaxial with the button before pressing it. This is however undesirable particularly in instruments used in automotive vehicles and operated by drivers, since such a procedure necessarily results in a certain loss of attention by the driver, affecting the safe driving of the vehicle.